DEVELOPING COUNTRIES: LAND USE AND WATER QUALITY AT RIVER BASIN

ZURINDA MAT RABU

 

Development in a country happens when there is a change of land use activities. All land uses have positive and negative impact to the environment. The water quality problems are often associated with land use changes. This study was done literary on river basins of eight countries namely Malaysia, Indonesia, Thailand, Bangladesh, China and India. These countries are known as Developing Countries. The objectives of this study are (1) to identify the relationship between rainfall and water quality (2) to compare the level of water qualities such as total suspended solid (TSS), turbidity, pH, biochemical oxygen demand (BOD), chemical oxygen demand (COD) and temperature with Interim National Water Quality Standard (INWQS) level of water quality.

 

The water quality will be affected due to the rain trend and the land use. Most developing countries are facing rapid population growths, land development, urbanisation and industrialization. These activities drastically change the land use from natural or rural to urban area (Mallin, 2009; Yusop et al, 2005). According to (Dong 2006; Tsegaye et al. 2006; Suthar et al. 2010), rapid urbanisation and economic development also cause the changes in the hydrology and ecology of river systems. Therefore the deterioration of water quality became the most serious problem in developing countries (Kido et al 2009).

 

 This study showed that rainfall had a major influence on the water quality. Rainfall is one of the most important parts of the hydrologic cycle. It is highly variable over time and space. According to Mallin et al. (2009) and Mandal et al. (2010), rainfall plays a major role for changing the water quality.       Water quality is one of the main characteristics of a river. Water, from the sources such as canals and rivers, is not only utilized as human water supply, but it also used for various activities such as transportation, tourism, and consumption (Areerachakul 2012).

 

The relationship between water quality (TSS) and rainfall is shown in Figure 1. The TSS value is significantly positively related to the rainfall at Chini Malaysia, Diwak Indonesia, Phong Thailand and Gangga India River Basins. However, data is not available for Bangladesh and China. Rainfall is expected to have high correlation with TSS at Thailand and India. The increased of river flow during wet season is responsible to transport more sediment into the river. According to Ekhwan et al. (2008), the TSS value increased during wet season due to the major sediment contributions mainly from land use activities and river bank erosion at Pahang River Basin Malaysia. From the study that was done by Sthiannopkao et al. (2007), the value of TSS was 10 times higher during wet season than dry season at Phong River Basin Thailand.

 

The water qualities of the Developing Countries were found to be in the Class II and III Category in the INWQS Table. The water quality of the Developed Countries however found to be in Class I Category in the INWQS Table. It can be concluded that the water quality of Developed Countries is much better and cleaner due to proper and well planned drainage and sewerage system. The water quality would become more severely polluted if Developing Countries failed to provide adequate and proper drainage and sewerage network system that will eventually lead to the rivers. Therefore, based on the conclusive review it is highly recommended that Developing Countries need to engage in a properly designed and planned network of drainage and sewerage system.